1. Field of the Invention
The invention relates to a drill with a drill shank and a bit, as well as a method for the manufacture thereof.
2. Prior Art
Drills for drilling metal are normally twist drills. The latter have a drill point, which has two bent bits, upstream of which are located flutes. The flutes extend helically over a considerable portion of the length of the drill shank. These twist drills are difficult to manufacture and require grinding after manufacture. Both the main cutting edges at the tip and the lateral secondary cutting edges adjacent to the flutes must be ground. Twist drills are expensive due to the complicated manufacture.
For some time now sheet metal has been used to an ever increasing extent in various branches of industry and even in those branches where the use of sheet metal has long been standard, the subsequent drilling of in particular small holes is becoming more common. Conventionally twist drills are used for this purpose. When they have become blunt, it is possible to regrind twist drills. However, this is generally only possible in workshops, the grinding equipment being unavailable to fitters or manual workers. Thus, frequently twist drills are thrown away instead of being reground. In addition, the small twist drills frequently break off in rough use.